It depends on the plug. There are two types,
afaik... the rubber coated rope, and a solid rubber plug. When I bought my 996, one of the rear tires had three plugs in it. And the guy was running it in DEs like that with no problem.
I don't think I would use the rubber coated rope for a repair on a tire to be tracked.
This (rubber coated rope)
versus this (mushroom plug)
More info-graphics:
